The present invention, developed during a joint research effort by FAA and NASA, relates to surface traffic management and the tracking, movement, and scheduling of multiple vehicles.
There is an ongoing, critical need for adequate surface traffic management to deal with increasing densities of road, water, air, and other surface traffic. Increased efforts by the research community are being made to cope with this accelerating challenge.
Airports are a critical venue for enhanced surface traffic management. Costs in departure taxi delays are $1.6 billion dollars a year in the U.S. alone. A number of airports face potential gridlock in the near future, in part due to these inefficiencies.
Various systems have been developed to improve information gathering, sharing, prediction, and use, in order to improve airport surface traffic management. These systems are a means to improve airport throughput and reduce the losses caused by inefficient taxi and runway queuing.
Surface traffic control systems in airports involve physical tracking of the aircraft. The systems use satellite tracking, surface radar tracking, infra-red tracking, diffusion field tracking, and other similar methods. Using such direct tracking methods, innovators have taught ways of identifying an aircraft's whereabouts after it has landed and before it has reached the gate, and after it has pushed back from the gate and before radar acquisition shortly after takeoff.
Tomita et al. (U.S. Pat. No. 5,670,961, issued Sep. 23, 1997) teach an airport surface traffic system which detects moving targets on an airport surface and automatically address identification codes to assist ground controllers and increase safety. This system incorporates some previously published flight schedule data. The Tomita et al. system is dependent on the presence of ground radar for surface tracking of aircraft.
Pilley et al. (U.S. Pat. No. 5,740,047, issued Apr. 14, 1998) disclose a GNSS (global navigational satellite system) multi-dimensional (3-D mapping plus time) management system used both for in-flight and surface aircraft control. The lynchpin of the system is the satellite-based location of aircraft, which allows for a zone-based incursion, alert, control, and scheduling system.
While the systems of Tomita et al. and Pilley et al., as well as other similar systems, are useful in helping with ground traffic management, airports still have a need for a system that provides real-time data acquisition and fusion from existing information sources and a taxiing efficiency predictive component. In response to this need, it has been suggested by a number of industry researchers that systems be developed that are not dependent on the deployment of additional tracking equipment.
Talley et al. (ASTA Traffic Planner System Description, Report 4J50-AHD-D001, Martin Marietta Corporation, Management and Data Systems, December 1993) describe proposed systems requirements for the ATP (ASTA Traffic Planner), an ASTA (Airport Surface Traffic Automation) system. Developing the capability to collect, integrate, and use different types of data from different domains of control is proposed. Methods for data acquisition, fusion, and prediction are not provided.
T. C. Meuninck reported a simple point-to-point data exchange test conducted at the Atlanta Airport wherein radar data was provided to the tower controllers. ("Finding the Pulse of the ATC System Heartbeat: A Joint Atlanta Airport/Local FAA/Aviation Users Adventure," Journal of ATC, January-March 1995, pp. 28-29.) Meunick's test suggested the potential workability of a data acquisition and fusion system. Additional work in surface taxi route planning has been developed and tested in Europe. The German TARMAC-PL system (Taxi and Ramp Management and Control--Planning), for example, uses a unified gate-to-takeoff taxi planning and route generation approach. (Winter, H. and Nusser, H.-G., Eds., Advanced Technologies for Air Traffic Flow Management, Bonn, Germany, April 1994, pp. 191-224. See also Klein, K., "Taxi and Ramp Management and Control," Institute of Flight Guidance, Internet: http:www.bs.dir.de/ff/fl/25/tarmac.htm, last modified Jun. 10, 1997, printed on Aug. 7, 1998.)
TARMAC may be the most mature and useful surface routing system currently in use. However, it would have limited application at U.S. and certain other airports. For instance, TARMAC is dependent on a variety of sensors that track actual ground aircraft position. Such sensors are generally lacking in U.S. and certain other airports. Also, TARMAC is functionally dependent on a level of communication and cooperation between different domains of control not found in the United States or in many other non-European countries.
TARMAC also has other limitations. For instance, it does not have a predictive element for on-ground aircraft location. Rather, TARMAC's predictive focus is on the shortest and most efficient taxi route from landing to takeoff.
The TMS system, a product of The Preston Group of Australia, also assists with surface route planning. ("TAAM Capabilities and Applications Overview Released," http://www.bs.dlr.de/ff/fl/25/tarmac.htm, last updated Jan. 1997, printed Aug. 7, 1998.) TMS uses software modeling to optimize the allocation of airport facilities and equipment such as aircraft stands, check-in desks, gate lounges, etc. SAIGA, a similar system developed in conjunction with ILOG SA, is a gate, stand, and belt allocation system. (Berger, R., "Constraint-Based Gate Allocation for Airports." http://www.ilog.com/papers/optimization/soluc32.pdf, last updated Sep. 26, 1997, printed Aug. 7, 1998.)
While considerable advancement has been made in surface traffic control over the last decade, the systems currently in use cannot be practically applied in United States and other airports having either minimal actual aircraft surface tracking data or a lack of communication and cooperation between different domains of control. The most mature of these systems are proprietary and therefore difficult to evaluate.
A system that predicts the locations, optimal taxiing, and departure queuing of on-the-ground aircraft by accessing, interpreting, and interpolating disparate existing data would be an important advancement in surface traffic management.